Here is an excerpt from the CMS press release:
CMS CLARIFIES GUIDELINES FOR NATIONAL PROVIDER IDENTIFIER (NPI) DEADLINE IMPLEMENTATION -- April 2, 2007
Today, the Centers for Medicare & Medicaid Services (CMS) announced that it is implementing a contingency plan for covered entities (other than small health plans) who will not meet the May 23, 2007, deadline for compliance with the National Provider Identifier (NPI) regulations under the Health Insurance Portability and Accountability Act (HIPAA) of 1996. The final rule establishing the NPI as the standard unique health provider identifier for health care providers was published in 2004 and requires all covered entities to be in compliance with its provisions by May 23, 2007, except for small health plans, which must be in compliance by May 23, 2008.
The enforcement guidance released today clarifies that covered entities that have been making a good faith effort to comply with the NPI provisions may, for up to 12 months, implement contingency plans that could include accepting legacy provider numbers on HIPAA transactions in order to maintain operations and cash flows.” said CMS Acting Administrator Leslie V. Norwalk, Esq. Emphasis added.